This invention relates to improved laboratory equipment used in performing scientific experiments such as those in the chemistry laboratory. The coupling system allows the traditional elements of laboratory equipment--flasks, distilling columns, thermometer adapters, distillation heads, vacuum adapters, etc.--to be joined by means of a polymeric or elastomeric connector which mates with a specially formed coupling flange on the various elements of apparatus. This coupling member is resistant to heat and chemicals, can be easily assembled and disassembled and yet resists being separated axially, is gas, liquid and vacuum tight, will not leak liquids or gases under moderate internal pressure, is lightweight, is capable of making the apparatus self-supporting and more easily assembled, and it can be cut from the apparatus should it become stuck. The coupling member and corresponding glass members are axially symmetrical allowing rotation about the axis during use. The coupling member is bilaterally symmetrical perpendicular to the axis; the joints so formed have no male or female character. The joint is not restricted in diameter and has the same interior diameter as the tubing from which it is made. This allows unrestricted passage of solids, liquids and vapors and allows various devices to pass through and operate within the joint, devices such as spinning bands for distillation, and piston-like devices such as squeegee-like cleaners, and movable filters.
Further, the present laboratory equipment provides a means for performing such experiments on a scale much smaller than present common practice. During the past thirty years, the scale at which experimental work has been carried out in the college chemistry laboratory, in particular, the organic chemistry laboratory, has not changed, yet the analytical instruments available have increased in sensitivity by one or two orders of magnitude. Newly available, relatively, inexpensive weighing equipment, now makes small scale experimentation routinely possible, but reasonably priced laboratory glassware is not available.
Experimentation on a small scale is becoming mandatory. During the past two decades, the awareness and concern over the dangers of exposure to toxic substances--carcinogens, teratogens, mutagens, poisons, etc.,--have increased substantially. Regulations promulgated by the United States Environmental Protection Agency (EPA) limit the legal exposure to toxic substances. Adequate ventilation must be provided to all workers and there are strict limits on the amounts of toxic substances with which a worker can come in contact, be it by ingestion, absorption through the skin, or inhalation.
It is desirable to make use of the traditional, pedagogically, sound experiments which have evolved in the teaching of chemistry. This can be done while also reducing worker exposure to toxic substances by carrying out the experiments on a scale ten to one hundred times smaller than is now done.
The problem of disposal of hazardous laboratory waste is reduced when experiments are conducted on a small scale. In addition, smaller scale experiments reduce the cost of conducting experiments by reducing the quantities of chemicals used as reagents and solvents in reactions and used to clean apparatus after a reaction is finished. This cost reduction is especially significant for academic laboratories where the cost of materials is becoming prohibitive.
The amount of energy needed to heat and cool small scale experiments is reduced. The amount of space needed to store equipment and to conduct experiments is also lessened, resulting in reduced capital costs for new laboratories. Perhaps, most importantly, the amount of ventilation needed in a laboratory is drastically reduced. It now costs $1200 per year to operate one laboratory hood for one year at the latitude of New York City. Current recommendations call for one hood for each two students carrying out organic chemical experiments.
The present invention meets the foregoing concerns by providing laboratory equipment having a specially-designed coupling system especially suited to small scale experimentation. In addition to the previously listed advantages, the invention provides numerous advantages over the larger laboratory glassware systems of the prior art and can be utilized as traditional size laboratory glassware systems as well as at the smaller scale.